<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2014 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
namespace Think\Cache\Driver;

use Think\Cache;

defined ( 'THINK_PATH' ) or exit ();
/**
 * Apachenote缓存驱动
 */
class Apachenote extends Cache {
	
	/**
	 * 架构函数
	 * 
	 * @param array $options
	 *        	缓存参数
	 * @access public
	 */
	public function __construct($options = array()) {
		if (! empty ( $options )) {
			$this->options = $options;
		}
		if (empty ( $options )) {
			$options = array (
					'host' => '127.0.0.1',
					'port' => 1042,
					'timeout' => 10 
			);
		}
		$this->options = $options;
		$this->options ['prefix'] = isset ( $options ['prefix'] ) ? $options ['prefix'] : C ( 'DATA_CACHE_PREFIX' );
		$this->options ['length'] = isset ( $options ['length'] ) ? $options ['length'] : 0;
		$this->handler = null;
		$this->open ();
	}
	
	/**
	 * 读取缓存
	 * 
	 * @access public
	 * @param string $name
	 *        	缓存变量名
	 * @return mixed
	 */
	public function get($name) {
		$this->open ();
		$name = $this->options ['prefix'] . $name;
		$s = 'F' . pack ( 'N', strlen ( $name ) ) . $name;
		fwrite ( $this->handler, $s );
		
		for($data = ''; ! feof ( $this->handler );) {
			$data .= fread ( $this->handler, 4096 );
		}
		N ( 'cache_read', 1 );
		$this->close ();
		return $data === '' ? '' : unserialize ( $data );
	}
	
	/**
	 * 写入缓存
	 * 
	 * @access public
	 * @param string $name
	 *        	缓存变量名
	 * @param mixed $value
	 *        	存储数据
	 * @return boolean
	 */
	public function set($name, $value) {
		N ( 'cache_write', 1 );
		$this->open ();
		$value = serialize ( $value );
		$name = $this->options ['prefix'] . $name;
		$s = 'S' . pack ( 'NN', strlen ( $name ), strlen ( $value ) ) . $name . $value;
		
		fwrite ( $this->handler, $s );
		$ret = fgets ( $this->handler );
		$this->close ();
		if ($ret === "OK\n") {
			if ($this->options ['length'] > 0) {
				// 记录缓存队列
				$this->queue ( $name );
			}
			return true;
		}
		return false;
	}
	
	/**
	 * 删除缓存
	 * 
	 * @access public
	 * @param string $name
	 *        	缓存变量名
	 * @return boolean
	 */
	public function rm($name) {
		$this->open ();
		$name = $this->options ['prefix'] . $name;
		$s = 'D' . pack ( 'N', strlen ( $name ) ) . $name;
		fwrite ( $this->handler, $s );
		$ret = fgets ( $this->handler );
		$this->close ();
		return $ret === "OK\n";
	}
	
	/**
	 * 关闭缓存
	 * 
	 * @access private
	 */
	private function close() {
		fclose ( $this->handler );
		$this->handler = false;
	}
	
	/**
	 * 打开缓存
	 * 
	 * @access private
	 */
	private function open() {
		if (! is_resource ( $this->handler )) {
			$this->handler = fsockopen ( $this->options ['host'], $this->options ['port'], $_, $_, $this->options ['timeout'] );
		}
	}
}